Parashat Hachodesh begins with the first commandment directed to the Israelites as a nation. They are commanded to designate Nisan as the first month and thereby institute a lunar calendar.
Commentators ask why the commandment to sanctify the months is included in this special pre-Pesach reading, rather than focusing solely on the later verses dealing specifically with the paschal sacrifice.
Ramban suggests that the commandment to implement a calendar only makes sense for a free nation. Slaves have no need to mark time, since they cannot control how they spend it. While we often complain that we are slaves to time, Ramban reminds us that the liberty to count time, and use it as we see fit, is the true symbol of freedom.
Rashi cites a charming midrash in which Moses is unclear what "the head of the months" means. So God points at the sliver of moon with His finger, instructing Moses, "When the moon looks like this you should sanctify it".
It might seem strange that the crescent moon should be sanctified, rather than a full moon at its most magnificent. But for people about to take their first steps towards nationhood, this must have been inspiring. They sanctify the moon as it begins its journey, tiny but full of potential. It is not the full brightness that is blessed, but the spark that holds the prospect of renewal.
Perhaps this is why the portion is read just before Pesach, when our attention turns towards children and their sense of wonder. We sanctify the crescent moon to remind us of the importance of engaging with children as they begin their Jewish journey. They hold the potential for our renewal and future national greatness.